A 10S galectin-3-U1 snRNP complex assembles into active spliceosomes.

ABSTRACT: In previous studies, we reported that fractionation of HeLa cell nuclear extracts on glycerol gradients revealed an endogenous ∼10S particle that contained galectin-3 and U1 snRNP and this particle was sufficient to load the galectin polypeptide onto a pre-mRNA substrate. We now document that this interaction between the galectin-3-U1 snRNP particle and the pre-mRNA results in a productive spliceosomal complex, leading to intermediates and products of the splicing reaction. Nuclear extracts were depleted of U1 snRNP with a concomitant loss of splicing activity. Splicing activity in the U1-depleted extract can be reconstituted by the galectin-3-U1 snRNP particle, isolated by immunoprecipitation of the 10S region (fractions 3-5) of the glycerol gradient with anti-galectin-3 antibodies. In co

SUBMITTER: Haudek KC 

PROVIDER: S-EPMC5291251 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature